60 f100 heater box?
 

I ran across a 60 f100 today. In the center below dash was a heater box that had three doors on it. the doors opened right and left and the bottom one lifted up. Is this an original box? what were the knobs on the doors made from? the unit had two small holes for screws. The outside of door had a enlongated hour glass shape for the knob. What knobs are these? And is this original?

That description does not sound at all like the standard recirculating heater, or the upgrade Fresh Aire heater. It must be aftermarket. I believe that all heaters were optional, i.e. not standard equipment. Can you take some photos?

Thanks for your response. I'll get pictures if possible, hopefully by the weekend.